1. The waterborne polyurethane resin is characterized by comprising the following components in parts by mass: 15-20 parts of isophorone diisocyanate, 5-15 parts of hydroxyl-terminated polybutadiene, 5-18 parts of an organic solvent, 5-12 parts of castor oil modified polyester polyol, 2-8 parts of a hydrophilic chain extender, 2-6 parts of a neutralizer, 0.4-5 parts of a rear chain extender, 0.01-0.25 part of a catalyst and 50-65 parts of deionized water.

2. The aqueous polyurethane resin according to claim 1, wherein the aqueous polyurethane resin comprises, in parts by mass: 15-20 parts of isophorone diisocyanate, 6-15 parts of hydroxyl-terminated polybutadiene, 5-15 parts of an organic solvent, 5-10 parts of castor oil modified polyester polyol, 3-8 parts of a hydrophilic chain extender, 2-5 parts of a neutralizer, 0.5-5 parts of a post-chain extender, 0.01-0.2 part of a catalyst and 50-60 parts of deionized water.

3. The aqueous polyurethane resin according to claim 1, wherein the hydrophilic chain extender is 1, 4-butanediol and the post-chain extender is 2, 2-dimethylolpropionic acid.

4. The aqueous polyurethane resin according to claim 1, wherein the organic solvent is acetone, the neutralizer is dimethylethanolamine, and the catalyst is organic bismuth.

5. The method for producing an aqueous polyurethane resin according to any one of claims 1 to 4, characterized by comprising the steps of:

adding hydroxyl-terminated polybutadiene, castor oil modified polyester polyol and a hydrophilic chain extender into a reaction kettle, heating to 100-140 ℃, performing vacuum dehydration, cooling to 40-60 ℃ under the protection of inert gas, adding isophorone diisocyanate and a catalyst, heating to 80-90 ℃, performing heat preservation for 2.5-4 h, adding a rear chain extender, heating to 90-100 ℃, and performing heat preservation reaction for 1-5 h; and cooling to 35-45 ℃, adding part of the neutralizer, uniformly stirring, adding the organic solvent, uniformly dispersing, adding deionized water and the neutralizer, uniformly stirring, and removing the organic solvent to obtain the waterborne polyurethane resin.

6. The low-temperature-resistant water-based PVC primer is characterized by comprising the following components in parts by mass: 80-90 parts of water-based polyurethane resin, 0.1-0.3 part of flatting agent, 0.1-0.3 part of defoaming agent, 0.1-0.3 part of thickening agent and 12-18 parts of deionized water.

7. The PVC primer according to claim 6, wherein the aqueous polyurethane resin comprises, in parts by mass: 15-20 parts of isophorone diisocyanate, 5-15 parts of hydroxyl-terminated polybutadiene, 5-18 parts of an organic solvent, 5-12 parts of castor oil modified polyester polyol, 2-8 parts of a hydrophilic chain extender, 2-5 parts of a neutralizer, 0.4-5 parts of a rear chain extender, 0.01-0.25 part of a catalyst and 50-65 parts of deionized water.

8. The PVC primer coating according to claim 6, wherein the hydrophilic chain extender is 1, 4-butanediol and the post-chain extender is 2, 2-dimethylolpropionic acid; the organic solvent is acetone, the neutralizer is dimethylethanolamine, and the catalyst is organic bismuth.

9. The PVC primer coating according to claim 7, wherein the preparation method of the aqueous polyurethane resin comprises the following steps: adding a hydrophilic chain extender into a reaction kettle, heating to 100-140 ℃, performing vacuum dehydration, cooling to 40-60 ℃ under the protection of inert gas, adding isophorone diisocyanate and a catalyst, heating to 80-90 ℃, preserving heat for 2.5-4 h, adding a rear chain extender, heating to 90-100 ℃, and preserving heat for 1-5 h; and cooling to 35-45 ℃, adding part of the neutralizer, uniformly stirring, adding the organic solvent, uniformly dispersing, adding deionized water and the neutralizer, uniformly stirring, and removing the organic solvent to obtain the waterborne polyurethane resin.

10. The preparation method of the low-temperature-resistant water-based PVC primer according to any one of claims 6 to 9, characterized by comprising the following steps: adding the waterborne polyurethane resin, the flatting agent, the defoaming agent, the thickening agent and the deionized water into a reaction kettle, and uniformly stirring to obtain the low-temperature-resistant waterborne PVC primer.

Background

The PVC water-based primer on the market at present is mainly imported from foreign countries, and the existing water-based primer is easy to be anti-adhered after being rolled, has poor peeling force with a bonding layer of a hot melt adhesive at low temperature, and is difficult to deliver in the next procedure. The resistance to migration of the plasticizer is not complete, resulting in the edge strip falling off from the substrate to which it is attached.

Patent CN108003300A discloses a modified polyurethane dispersion for preparing a PVC edge banding treating agent, which is prepared by polymerizing raw materials, wherein the raw materials comprise, by mass: 10-20% of diisophorone diisocyanate, 6-15% of polymeric polyol, 2-10% of a hydrophilic chain extender, 1-4% of a first neutralizer, 0.01-0.1% of a metal catalyst, 2-15% of an organic solvent, 5-15% of a vinyl monomer, 1-4% of a second neutralizer, 0.5-2% of a post chain extender, 0.01-0.5% of an initiator and the balance of water. The PVC edge banding has good adhesive force, can effectively prevent plasticizer migration in PVC, so that the PVC edge banding and a plate are adhered together more tightly, but the PVC edge banding does not have low-temperature and high-humidity resistance, and the application of the PVC edge banding and the plate in low-temperature and cold environments is limited.

Patent CN104927747A discloses an aqueous polyurethane hot melt adhesive, a preparation method and application thereof, and specifically discloses a preparation method of the aqueous polyurethane hot melt adhesive, which comprises the following steps: (1) adding polyether polyol into a reaction kettle, heating to 120-130 ℃, keeping the temperature for dewatering, and cooling to 75-85 ℃; (2) under the condition of stirring, uniformly dropwise adding a catalyst into the reaction kettle in the step (1), then adding the isophorone diisocyanate, heating to 80-88 ℃ after the temperature is stable, and carrying out heat preservation reaction for 2.0-2.5 h to obtain a mixture; (3) dropwise adding a carboxyl monomer solution into the reaction kettle filled with the mixture in the step (2), adjusting the temperature to 80-90 ℃ after dropwise adding, and carrying out heat preservation reaction for 3-4 h to obtain a crude product; wherein the carboxyl monomer solution is obtained by dissolving a carboxyl monomer in an organic solvent; (4) and (3) adding acetone into the crude product obtained in the step (3) to reduce the system viscosity, increasing the rotating speed of a stirrer, cooling to 35-40 ℃, adding a neutralizing agent for neutralization, discharging, adding distilled water, carrying out high-speed shearing emulsification, and carrying out rotary evaporation to obtain the waterborne polyurethane hot melt adhesive. The melting point of the adhesive film is 130-150 ℃, and the adhesive film cannot be used at low temperature.

Disclosure of Invention

The invention provides a waterborne polyurethane resin and a low-temperature-resistant waterborne PVC primer, which have good low-temperature resistance and low-temperature and high-humidity resistance.

The invention adopts the following technical scheme for solving the technical problems:

an aqueous polyurethane resin comprises the following components in parts by mass: 15-20 parts of isophorone diisocyanate, 5-15 parts of hydroxyl-terminated polybutadiene, 5-18 parts of an organic solvent, 5-12 parts of castor oil modified polyester polyol, 2-8 parts of a hydrophilic chain extender, 2-6 parts of a neutralizer, 0.4-5 parts of a rear chain extender, 0.01-0.25 part of a catalyst and 50-65 parts of deionized water.

As a preferable scheme, the aqueous polyurethane resin comprises the following components in parts by mass: 15-20 parts of isophorone diisocyanate, 6-15 parts of hydroxyl-terminated polybutadiene, 5-15 parts of an organic solvent, 5-10 parts of castor oil modified polyester polyol, 3-8 parts of a hydrophilic chain extender, 2-5 parts of a neutralizer, 0.5-5 parts of a post-chain extender, 0.01-0.2 part of a catalyst and 50-60 parts of deionized water.

As a preferable scheme, the hydrophilic chain extender is 1, 4-butanediol, and the post chain extender is 2, 2-dimethylolpropionic acid.

The inventor of the invention finds that hydroxyl-terminated polybutadiene has good high adhesion and low temperature resistance in a large amount of formula researches of aqueous polyurethane resin, castor oil modified polyester polyol has strong crystallinity and excellent high temperature and high humidity resistance, and the castor oil modified polyester polyol and isophorone diisocyanate react to generate interpenetrating network structure resin which has good low temperature and high humidity resistance after film forming so as to have good adhesion under low temperature and high humidity.

The inventor further discovers in a great deal of research that under the formula system of the invention, the addition reaction of the hydrophilic chain extender (1, 4-butanediol) and the post chain extender (2, 2-dimethylolpropionic acid) generates a cured product with a three-dimensional network structure, further improves the low-temperature and high-humidity resistance, and ensures that the cured product has good adhesion at low temperature and high humidity.

Meanwhile, the inventors have found that the low-temperature and high-humidity resistance is significantly reduced by replacing the castor oil-modified polyester polyol and the hydroxyl-terminated polybutadiene with another polyester polyol. That is, only by combining hydroxyl-terminated polybutadiene, castor oil modified polyester polyol, isophorone diisocyanate, a hydrophilic chain extender (1, 4-butanediol) and a rear chain extender (2, 2-dimethylolpropionic acid), good adhesion can be achieved at low temperature and high humidity.

In the present invention, the hydroxyl-terminated polybutadiene is purchased from Nippon Caoda corporation under the designations JP-100, JP-200, GI-2000 and GI-3000.

In the present invention, the castor oil modified polyester polyol is purchased from Vanderues, U.S. designations D1000, D2000, D3000.

As a preferable scheme, the organic solvent is acetone, the neutralizing agent is dimethylethanolamine, and the catalyst is organic bismuth.

The invention also provides a preparation method of the waterborne polyurethane resin, which comprises the following steps:

adding hydroxyl-terminated polybutadiene, castor oil modified polyester polyol and a hydrophilic chain extender into a reaction kettle, heating to 100-140 ℃, performing vacuum dehydration, cooling to 40-60 ℃ under the protection of inert gas, adding isophorone diisocyanate and a catalyst, heating to 80-90 ℃, performing heat preservation for 2.5-4 h, adding a rear chain extender, heating to 90-100 ℃, and performing heat preservation reaction for 1-5 h; and cooling to 35-45 ℃, adding part of the neutralizer, uniformly stirring, adding the organic solvent, uniformly dispersing, adding deionized water and the neutralizer, uniformly stirring, and removing the organic solvent to obtain the waterborne polyurethane resin.

The invention also provides a low-temperature-resistant water-based PVC primer which comprises the following components in parts by mass: 80-90 parts of water-based polyurethane resin, 0.1-0.3 part of flatting agent, 0.1-0.3 part of defoaming agent, 0.1-0.3 part of thickening agent and 12-18 parts of deionized water.

In the invention, the leveling agent is Hydropalat WE 3120; the defoamer is Fomaster NO 2306, the thickener is Rheovis PU1331, and the thickener is purchased from Basff.

As a preferable scheme, the aqueous polyurethane resin comprises the following components in parts by mass: 15-20 parts of isophorone diisocyanate, 5-15 parts of hydroxyl-terminated polybutadiene, 5-18 parts of an organic solvent, 5-12 parts of castor oil modified polyester polyol, 2-8 parts of a hydrophilic chain extender, 2-5 parts of a neutralizer, 0.4-5 parts of a rear chain extender, 0.01-0.25 part of a catalyst and 50-65 parts of deionized water.

As a preferable scheme, the hydrophilic chain extender is 1, 4-butanediol, and the post chain extender is 2, 2-dimethylolpropionic acid; the organic solvent is acetone, the neutralizer is dimethylethanolamine, and the catalyst is organic bismuth.

As a preferable scheme, the preparation method of the aqueous polyurethane resin comprises the following steps: adding a hydrophilic chain extender into a reaction kettle, heating to 100-140 ℃, performing vacuum dehydration, cooling to 40-60 ℃ under the protection of inert gas, adding isophorone diisocyanate and a catalyst, heating to 80-90 ℃, preserving heat for 2.5-4 h, adding a rear chain extender, heating to 90-100 ℃, and preserving heat for 1-5 h; and cooling to 35-45 ℃, adding part of the neutralizer, uniformly stirring, adding the organic solvent, uniformly dispersing, adding deionized water and the neutralizer, uniformly stirring, and removing the organic solvent to obtain the waterborne polyurethane resin.

The invention also provides a preparation method of the low-temperature-resistant water-based PVC primer, which comprises the following steps: adding the waterborne polyurethane resin, the flatting agent, the defoaming agent, the thickening agent and the deionized water into a reaction kettle, and uniformly stirring to obtain the low-temperature-resistant waterborne PVC primer.

The invention has the beneficial effects that: the low-temperature-resistant water-based PVC primer prepared from the water-based polyurethane resin has good low-temperature-resistant and high-humidity-resistant performances, is scientific and simple in formula, has good adhesion force under low-temperature and high-humidity conditions after being optimized, and has good low-temperature-resistant and high-humidity-resistant performances after being formed into a film by using hydroxyl-terminated polybutadiene and castor oil modified polyester polyol to react with isophorone diisocyanate to generate interpenetrating network-structure resin.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, unless otherwise specified, the parts are all parts by mass.

Example 1

An aqueous polyurethane resin comprises the following components in parts by mass: 20 parts of isophorone diisocyanate, 15 parts of hydroxyl-terminated polybutadiene, 15 parts of acetone, 10 parts of castor oil modified polyester polyol, 8 parts of 1, 4-butanediol, 4 parts of dimethylethanolamine, 5 parts of 2, 2-dimethylolpropionic acid, 0.05 part of organic bismuth and 60 parts of deionized water.

In this example, the hydroxyl-terminated polybutadiene was purchased from Nippon Caoda corporation under the designation JP-200.

In this example, the castor oil-modified polyester polyol is purchased from Vanderues, U.S. under the designation D2000.

The preparation method of the waterborne polyurethane resin comprises the following steps:

adding hydroxyl-terminated polybutadiene, castor oil modified polyester polyol and 1, 4-butanediol into a reaction kettle, heating to 130 ℃, carrying out vacuum dehydration for 2h, cooling to 50 ℃ under the protection of inert gas, adding isophorone diisocyanate and organic bismuth, heating to 85 ℃, carrying out heat preservation for 3.5h, adding 2, 2-dimethylolpropionic acid, heating to 95 ℃, and carrying out heat preservation reaction for 4 h; cooling to 40 ℃, adding 50% of dimethylethanolamine by mass, uniformly stirring, adding acetone, uniformly dispersing, adding deionized water and the rest dimethylethanolamine, uniformly stirring, and removing the acetone to obtain the waterborne polyurethane resin.

Preparing a low-temperature-resistant water-based PVC primer: 85 parts by mass of the prepared waterborne polyurethane resin, 0.2 parts by mass of Hydropagat WE3120, 0.2 parts by mass of Fomaster NO 2306, 0.2 parts by mass of Rheovis PU1331 and 15 parts by mass of deionized water are added into a reaction kettle and stirred uniformly at 2000rpm to obtain the low temperature resistant waterborne PVC primer.

In the embodiment, hydroxyl-terminated polybutadiene has good high adhesion and low temperature resistance, the castor oil modified polyester polyol has strong crystallinity and excellent high temperature and high humidity resistance, the two are reacted with isophorone diisocyanate to generate interpenetrating network resin, the interpenetrating network resin has good low temperature and high humidity resistance after film formation, so that the castor oil modified polyester polyol has good adhesion at low temperature and high humidity, and the hydrophilic chain extender (1, 4-butanediol) and the post chain extender (2, 2-dimethylolpropionic acid) are added and reacted to generate a cured product with a three-dimensional network structure, so that the low temperature and high humidity resistance is further improved, and the castor oil modified polyester polyol has good adhesion at low temperature and high humidity.

Example 2

An aqueous polyurethane resin comprises the following components in parts by mass: 15 parts of isophorone diisocyanate, 6 parts of hydroxyl-terminated polybutadiene, 5 parts of acetone, 5 parts of castor oil modified polyester polyol, 3 parts of 1, 4-butanediol, 2 parts of dimethylethanolamine, 0.5 part of 2, 2-dimethylolpropionic acid, 0.05 part of organic bismuth and 50 parts of deionized water.

In this example, the hydroxyl-terminated polybutadiene was purchased from Nippon Caoda corporation under the designation JP-100.

In this example, the castor oil-modified polyester polyol is purchased from Vanderues, U.S. under the designation D1000.

The preparation method of the waterborne polyurethane resin comprises the following steps:

adding hydroxyl-terminated polybutadiene, castor oil modified polyester polyol and 1, 4-butanediol into a reaction kettle, heating to 130 ℃, carrying out vacuum dehydration for 2h, cooling to 50 ℃ under the protection of inert gas, adding isophorone diisocyanate and organic bismuth, heating to 85 ℃, carrying out heat preservation for 3.5h, adding 2, 2-dimethylolpropionic acid, heating to 95 ℃, and carrying out heat preservation reaction for 4 h; cooling to 40 ℃, adding 50% of dimethylethanolamine by mass, uniformly stirring, adding acetone, uniformly dispersing, adding deionized water and the rest dimethylethanolamine, uniformly stirring, and removing the acetone to obtain the waterborne polyurethane resin.

Preparing a low-temperature-resistant water-based PVC primer: 85 parts by mass of the prepared waterborne polyurethane resin, 0.2 parts by mass of Hydropagat WE3120, 0.2 parts by mass of Fomaster NO 2306, 0.2 parts by mass of Rheovis PU1331 and 15 parts by mass of deionized water are added into a reaction kettle and stirred uniformly at 2000rpm to obtain the low temperature resistant waterborne PVC primer.

Example 3

An aqueous polyurethane resin comprises the following components in parts by mass: 18 parts of isophorone diisocyanate, 12 parts of hydroxyl-terminated polybutadiene, 10 parts of acetone, 8 parts of castor oil modified polyester polyol, 5 parts of 1, 4-butanediol, 2.5 parts of dimethylethanolamine, 3 parts of 2, 2-dimethylolpropionic acid, 0.05 part of organic bismuth and 55 parts of deionized water.

In this example, the hydroxyl-terminated polybutadiene is purchased from Nippon Caoda corporation under the designation GI-2000.

In this example, the castor oil-modified polyester polyol is purchased from Vanderues, U.S. under the designation D1000.

The preparation method of the waterborne polyurethane resin comprises the following steps:

adding hydroxyl-terminated polybutadiene, castor oil modified polyester polyol and 1, 4-butanediol into a reaction kettle, heating to 130 ℃, carrying out vacuum dehydration for 2h, cooling to 50 ℃ under the protection of inert gas, adding isophorone diisocyanate and organic bismuth, heating to 85 ℃, carrying out heat preservation for 3.5h, adding 2, 2-dimethylolpropionic acid, heating to 95 ℃, and carrying out heat preservation reaction for 4 h; cooling to 40 ℃, adding 40% of dimethylethanolamine by mass, uniformly stirring, adding acetone, uniformly dispersing, adding deionized water and the rest dimethylethanolamine, uniformly stirring, and removing the acetone to obtain the waterborne polyurethane resin.

Preparing a low-temperature-resistant water-based PVC primer: 85 parts by mass of the prepared waterborne polyurethane resin, 0.2 parts by mass of Hydropagat WE3120, 0.2 parts by mass of Fomaster NO 2306, 0.2 parts by mass of Rheovis PU1331 and 15 parts by mass of deionized water are added into a reaction kettle and stirred uniformly at 2000rpm to obtain the low temperature resistant waterborne PVC primer.

Example 4

Example 4 differs from example 1 in that example 4 uses the same amount of ethylene glycol instead of 1, 4-butanediol and the same amount of ethylene diamine instead of 2, 2-dimethylolpropionic acid, all else being the same, i.e. in this example the hydrophilic chain extender and the post-chain extender are replaced by ethylene glycol, ethylene diamine.

Comparative example 1

Comparative example 1 differs from example 1 in that comparative example 1 uses the same amount of polycaprolactone diol (molecular weight 1000) in place of the castor oil-modified polyester polyol of example 1, all else being identical.

Comparative example 2

Comparative example 2 differs from example 1 in that comparative example 2 uses an equal amount of polybutadiene instead of the hydroxyl-terminated polybutadiene described in example 1, all else being equal.

Comparative example 3

Comparative example 3 is different from example 1 in that in comparative example 3, the modified polyurethane dispersant prepared in example 1 of CN108003300A is used to replace the aqueous polyurethane resin described in example 1, and the rest is the same.

To further demonstrate the effect of the present invention, the following test methods were provided:

the primer described in each example and comparative example is respectively coated on a PVC edge banding (3 test examples are selected for each example and comparative example, the test is carried out on the primer, the PVC edge banding coated with the primer and a high-density plate are heat-sealed and attached by using a hot melt adhesive, construction is respectively carried out at different environmental temperatures, after one week of gluing, the low-temperature resistance is detected at-10 ℃ after one week of gluing, the low-temperature and high-humidity resistance is detected at 0 ℃ and the humidity of 80%, and the test results are shown in table 1 after one week of gluing.

TABLE 1 test results

As can be seen from Table 1, the low-temperature-resistant PVC primer prepared from the waterborne polyurethane resin has good low-temperature resistance and low-temperature and high-humidity resistance.

As can be seen from comparative examples 1 to 3, the PVC primer prepared from the waterborne polyurethane resin with the optimized formula has good low-temperature resistance and low-temperature and high-humidity resistance.

Comparing example 1 with example 4, it can be seen that, under the formula system of the present invention, the selection of different hydrophilic chain extenders and post chain extenders can also affect the low temperature resistance and the low temperature and high humidity resistance to a certain extent, wherein the 1, 4-butanediol and 2, 2-dimethylolpropionic acid according to the present invention have better applicability, and have better low temperature resistance and low temperature and high humidity resistance.

As can be seen from comparison of example 1 with comparative examples 1 and 2, if the castor oil-modified polyester polyol of the present invention is replaced with another substance or the hydroxyl-terminated polybutadiene is replaced with another substance, the low temperature resistance and the low temperature and high humidity resistance are both significantly reduced.

It can be seen that good adhesion can be achieved at low temperature and high humidity only by combining hydroxyl-terminated polybutadiene, castor oil modified polyester polyol, isophorone diisocyanate, a hydrophilic chain extender (1, 4-butanediol), and a post chain extender (2, 2-dimethylolpropionic acid).

In light of the foregoing description of preferred embodiments according to the invention, it is clear that many changes and modifications can be made by the person skilled in the art without departing from the scope of the invention. The technical scope of the present invention is not limited to the contents of the specification, and must be determined according to the scope of the claims.